There is the "Upper Realm of Fairyland" and the "Lower Realm of Kyushu". The resources in the lower realm are scarce and spiritual energy is thin, so the monks will do whatever they can to achieve ascension. In order to maintain its rule, the fairy court in the upper realm regularly "harvested" potential monks and resources in the lower realm, and regarded the lower realm as a source of soldiers and mines. There is a "natural chasm" separating the two realms, which can only be crossed by passing the "immortal ladder" descended from the fairy court or finding the ancient secret path.
